Self-destructible fuze

ABSTRACT

A mechanical device for use in self-destruction of a mine, said device being a spring-loaded withdrawal pin separately engaging a mating slot in a spring-loaded firing pin wherein withdrawal is actuated by the disintegration of the structural integrity of a rigid hydroscopic material upon the absorption of moisture.

[4 1 June 19, 1973 United States Patent 1 Heinemann.

[ SELF-DESTRUCTIBLE FUZE [75] Inventor:

2,741,182 4/1956 Faust et a1. Robert W. Heinernann, Dover, NJ. 12/196 at al [73] Assignee: The United States of America as Primary Examine, BenJ-amin Borchelt frai wzgh ggigifggf of the Assistant Examiner-Thomas H Webb Feb. 9, 1968 [21] App]. No.: 707,375

Attorney--Harry M. Saragovitz, Herbert Ber], Edward- J. Kelly and Edward F. Costigan [22] Filed:

102/70 A mechanical device for use in self-destruction of a 2 10 6 mine, said device being a spring-loaded withdrawal pin i separately engaging a mating slot in a spring-loaded firing pin wherein withdrawal is actuated by the disinte- [51] Int. CL... F42c 15/36, F42c 19/08, F42c 15/00 [58] Field of Search........................ 102/1 56] References Cited gration of the structural integrity of a rigid hydroscopic UNITED STATES PATENTS material upon the absorption of moisture.

102/70 1 Claim, 1 Drawing Figure Patented June 19, 1973 1 N VEN TOR.

ROBERT m HE/NEMA/VN A TTORNEY5 SELF-DESTRUCTIBLE FUZE This invention relates to a device for use in the selfdestruction of a mine.

During various stages of warfare, a multitude of items of destruction such as mines and the like are heavily sown in various sectors of the battlefield. Under present practice, there may be as many as a million mines emplaced at one time by means of an air-to-ground delivery system. Of those sown, the average number of duds, which may still be classed as live ammunition, is extremely high. However, a problem arises, after cessation of hostilities, when it is otherwise customary for the populace to reoccupy the area. Each of the duds must be individually deactivated for safety. In the past, it has been found that it requires years to clear an area which has been subjected to mining in moderation. How long would it take to clear an area of duds, which under present practice has been subjected to heavy sowing of items of destruction such as mines and the like? In France, for example, there are areas, which were sown with mines during World War II which are still closed to the public for their protection. Another good example is Germany, where, after 25 years, they are still deactivating the shells which fell upon the battlefield in the early forties.

The present invention answers the needs of the art by providing a destruct feature for use on mines which will become activated after a predetermined period of time. In this manner, each of the million or so mines will be destroyed after a predetermined period of time if not otherwise previously activated by opposing forces in the sector under attack. This insures that after a predetermined period of time, both friendly forces and the populace may occupy the area without incident.

It is an object of this invention to provide a device for the destruction of a mine after a predetermined period of time.

Another object is to provide a chemically-actuated mechanical device for use in the destruction of a mine.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

The drawing is a side view, in section, of the device of this invention.

The device of this invention as shown in the drawing, is provided with a spring-loaded firing pin 1 1 restrained from firing into an initiator 12 by means of a withdrawal pin 13 to one end of which a spring-loaded base 15 is integrally affixed. The free end 16 of the withdrawal pin 13 is slidably fitted into a mating slot 17 provided in the spring-loaded firing pin 11. The base 15 rests on a rigid, solidified hydroscopic structure 18, which prevents the downward movement of the base 15 and the consequent downward movement and withdrawal of pin 13 from slot 17. Upon exposure of the mine to the atmosphere, the hydroscopic material 18 will draw moisture out of the air through defined size channels or inlets 19 in the device. As a result of the absorption of moisture, the rigid structure 18 will become wet and soggy and will eventually lose structural integrity. The spring-loaded base 15 will then move in a downwardly direction by the action of spring 21 against the disintegrating structural foundation of the hydroscopic material 18 and, as a consequence, pin 13 will be withdrawn from slot 17. When pin 13 is clear of slot 17, the firing pin 11 will move in a forwardly direction against the initiaotr 12 by the action initiator spring 22. As a result, the mine will explode and will no longer function as a hazard to the populace if at some future date, they desire to occupy the area.

It should be noted that some cases exist in the use of munitions which do not readily lend themselves towards the absorption of water from the atmosphere as part of a sterilization or self-destruct mechanism. This is generally due to the structure of the mine itself. In such cases, it is possible to carry the water along in the munition itself as part of the destruct device. Thus, the water may be encapsulated within a glass or plastic ampule which will break upon deployment or after deployment of the munition thereby placing it in contact with the reactive hydroscopic material 18. Such material 18 may be chemically treated to prevent its immediate reaction with water and, as a consequence, an induction period can be introduced before the reaction or disintegration of the material can proceed. This induction period may be designed for a specified period and provides a mechanism for obtaining a delayed reaction leading to self-sterilization or self-destruction.

The water capsule itself may contain additional materials, such as ethylene glycol or methanol to permit the capsule to remain stable at low temperatures. The ampule itself may be constructed of glass or plastic. It may have a variety of shapes, such as spherical or cylindrical. It may, in addition, be stressed or notched in order to simplify its break-up upon deployment. Also, the control of time to self-sterilization or destruction will be a function of the type of coating placed upon the reactive material, its thickness and solubility. Thicker and less soluble materials will tend to increase the time function, while thinner and more soluble materials will tend to decrease it.

The hydroscopic materials which may be used to advantage within this concept include lithium chloride, sodium hydroxide, potassium thiosulfate, potassium monobasic and dibasic phosphate, potassium hydroxide, potassium hypophosphite and ammonium biphosphite.

I claim:

1. In a mine having an auxiliary spring-loaded firing pin for engagement with an initiator, the improvement of a spring-loaded withdrawal pin slidably fitted into a mating slot in said firing pin,

a base integral with said withdrawal pin, and

a solidified rigid mass of hydroscopic material supporting said base,

said solidified rigid mass being convertible in situ to a fluidized mass. 

